AB1518 CASE REPORT OF A HARD TO TREAT DERMATOMYOSITIS AFTER A COVID-19 INFECTION AND SUBSEQUENT VACCINATION
Authors: P. Peteva, L. Marinchev
Journal: Annals of the Rheumatic Diseases (2022)

Background A 50 years old woman, a medical doctor, came to our department with symmetrical proximal muscular weakness, several months after Covid-19 infection and three weeks after a second dose of Covid-19 mRNA vaccine. The patient had no prior or family history of autoimmune diseases and take no medicines. In the past she undergone an operation for double-kidney with frequent urinary infections. Objective findings have shown symmetrical proximal muscular weakness and classic sings of dermatomyositis - Gottron’s papules, shawl and holster signs, periungual vasculitis. Objectives We present a case of a 50 old woman with clinical and laboratory proven dermatomyositis, starting three weeks after a second dose of a Covid1-19 mRNA vaccine without other reasons. Methods The laboratory tests showed elevated CPK, lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase, high ANA – 1:1280 and myositis specific autoantibodies- anti-NXP2 and anti-Mi-2- beta. The electromyography showed myopathic changes and the muscle MRI – symmetrical edema of mm.obturator and mm.adductor brevis. We exclude diseases that may mimic inflammatory myopathies. We made a cancer screening – whole body MRI, colonoscopy, gastroscopy, mammography and gynecological exam, immunoblot for detection of paraneoplastic syndrome-associated neuronal antibodies, with no detection of cancer. Muscle biopsy of m.vastus lateralis showed attenuating muscle inflammation with advancing muscle atrophy and fibrosis. Results The diagnose dermatomyositis was made according Bohan and Peter criteria and we start a high dose (1mg/kg/day) glucocorticoid therapy with good initial clinical and laboratory effect. Two months after starting a therapy muscle weakness worsened together with difficulty of swallowing. We excluded steroid myopathy after second EMG and lack of improvement when tapering the GS dose. Methotrexate 20 mg/weekly was added as a steroid sparing drug with good response, but was stopped because flare of pyelonephritis. Accordning to the opinion of dermatologist hydroxychloroquine was started for a couple of weeks, because of active skin manifestations. Muscle weakness worsened on the background of treatment, which was stopped. We started a therapy with intravenous immunoglobulins and considered therapy with cyclophosphamide or azathioprine after urinary infection. Because the patient was infected for a second time with covid-19, although vaccine, we continued only with glucocorticoids and antiosteoporotic therapy. Conclusion The etiology and pathogenesis of inflammatory myopathies are not fully clarified so far. We speculate that the infection with Covid-19 as well as mRNA vaccine trigger inflammatory myopathy and compromise the patient’s immunity for poor treatment response with glucocorticoids and immunosuppressives. On the other hand advanced muscle atrophy and fibrosis within a short period show that suspected triggering factors could be a reason for difficult to treat such type of dermatomyiositis. Disclosure of Interests None declared